Publications by authors named "Mostafa A Hamad"

Roux-en-Y hepaticojejunostomy (RYHJ) with the provision of "gastric access loop" was developed to shorten the distance traveled by the endoscope to reach hepaticojejunostomy (HJ) anastomotic site. The aim of our study was to assess modified RYHJ with gastric access loop (RYHJ-GA) and compare it with conventional RYHJ (RYHJ-C) regarding short- and long-term outcomes and, moreover, to evaluate the feasibility and results of future endoscopic access of the modified bilio-enteric anastomosis. Patients eligible for RYHJ between September 2017 and December 2019 were allocated randomly to receive either RYHJ-C or RYHJ-GA.

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Objectives: Intraoperative bleeding is commonly encountered during living donor liver transplant procedures and is associated with greater need for blood transfusion, which increases morbidity. Herein, we hypothesized that early and continuous occlusion ofthe hepatic inflow would have a beneficial effect on the living donor liver transplant procedure regarding intraoperative blood loss and operative time.

Materials And Methods: This comparative study prospectively included 23 consecutive patients (the experimental group) who had early inflow occlusion during recipient hepatectomy for living donor liver transplant and compared the outcomes versus 29 consecutive patients who had previously received (immediately before the start of our study) living donor liver transplant by the classic technique.

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Background: Roux-en-Y hepaticojejunostomy (RYHJ) is usually required for major bile duct injury (BDI) as a definitive treatment. Hepaticojejunostomy anastomotic stricture (HJAS) is the most feared long-term complication following RYHJ. The ideal management of HJAS remains undefined.

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Hemorrhage is a prime cause of death in civilian and military traumatic injuries, whereby a significant proportion of death and complications occur prior to paramedic arrival and hospital resuscitation. Hence, it is crucial to develop hemostatic materials that are able to be applied by simple processes and allow control over bleeding by inducing rapid hemostasis, non-invasively, until subjects receive necessary medical care. This review discusses recent advances in synthesis and fabrication of degradable hemostatic nanomaterials and nanocomposites.

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Zwitterionic polymer nanoparticles of diverse morphologies (spherical, cylindrical, and platelet-like) constructed from biocompatible sugar-based polymers are designed to extend the pharmacological activities of short- and long-acting insulin peptides, thereby providing potential for therapeutic systems capable of reducing the frequency of administration and improving patient compliance. Amphiphilic block copolymers composed of zwitterionic poly(d-glucose carbonate) and semicrystalline polylactide segments were synthesized, and the respective block length ratios were tuned to allow formation of nanoscopic assemblies having different morphologies. Insulin-loaded nanoparticles had similar sizes and morphologies to the unloaded nanoparticle counterparts.

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In the current study, hemostatic compositions including a combination of chitosan and kaolin have been developed. Chitosan is a marine polysaccharide derived from chitins, a structural component in the shells of crustaceans. Both chitosan and kaolin have the ability to mediate a quick and efficient hemostatic effect following immediate application to injury sites, and thus they have been widely exploited in manufacturing of hemostatic composites.

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The aims of the current study were to develop insulin-loaded nanoparticles comprised of various polymers at different compositions, and to evaluate their ability to lower blood glucose levels in diabetic rats following subcutaneous and oral administrations. Several combinations of natural and synthetic polymers have been utilized for preparation of nanoparticles including, chitosan, alginate, albumin and Pluronic. Nanosized (170 nm-800 nm) spherical particles of high encapsulation efficiency (15-52%) have been prepared.

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Objectives: Drug incompatibilities may compromise the safety and effectiveness of combined drugs and result in mild-to-serious clinical complications, such as catheter obstruction, loss of drug efficacy, formation of toxic derivatives and embolism. Various preventive strategies have been implemented to overcome drug incompatibilities with limited success. This review presents an innovative approach to prevent drug incompatibilities via isolating the incompatible drugs into nanostructures.

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The development of hemostatic technologies that suit a diverse range of emergency scenarios is a critical initiative, and there is an increasing interest in the development of absorbable dressings that can be left in the injury site and degrade to reduce the duration of interventional procedures. In the current study, β-cyclodextrin polyester (CDPE) hydrogels serve as sacrificial macroporous carriers, capable of degradation under physiological conditions. The CDPE template enables the assembly of imprinted chitosan honeycomb-like monolithic mats, containing highly entangled nanofibers with diameters of 9.

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Albumin is used as a plasma expander in critically ill patients and for several other clinical applications mainly via intravenous infusion. Oral administration of albumin can improve patient compliance although limited oral bioavailability of proteins is still a major challenge. Although nanomaterials have been extensively utilized for improving oral delivery of proteins, albumin has been utilized only as either a model drug or as a carrier for drug delivery.

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Antimicrobial resistance is one of the most significant health challenges worldwide. Meropenem is a broad spectrum beta-lactam antibiotic that possesses high activity against Gram-positive and Gram-negative bacteria. However, it has a short plasma half-life, and thus requiring frequent administration of high doses.

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Drug incompatibilities are considered as one of the most critical problems in intensive care units. In the current study, the ability of nanomaterials to prevent drug incompatibilities in clinical settings has been investigated. As a proof-of-concept, the ability of niosomes to prevent physical and chemical incompatibilities that occur upon mixing acyclovir and vancomycin during management of acute meningitis has been explored.

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Background: Pancreatic pseudocyst (PP) is the commonest cystic lesion of the pancreas. Internal drainage of PPs can be accomplished by traditional open or recently by minimally invasive laparoscopic or endoscopic approaches. We aimed to evaluate and compare the clinical outcomes after endoscopic, laparoscopic, and open drainage.

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Nucleic acids therapeutic efficiency is generally limited by their low stability and intracellular bioavailability, and by the toxicity of the carriers used to deliver them to the target sites. Aminated poly(glycerol methacrylate) polymers are biodegradable and pH-sensitive polymers that have been used previously to deliver antisense oligonucleotide and show high transfection efficiency. The purpose of this study is to compare the efficiency and toxicity of aminated linear poly(glycerol methacrylate) (ALT) biodegradable polymer to the most commonly used cationic degradable (i.

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Delivery of multiple therapeutics and/or diagnostic agents to diseased tissues is challenging and necessitates the development of multifunctional platforms. Among the various strategies for design of multifunctional nanocarriers, biodegradable polyphosphoester (PPE) polymers have been recently synthesized via a rapid and simple synthetic strategy. In addition, the chemical structure of the polymer could be tuned to form nanoparticles with varying surface chemistries and charges, which have shown exceptional safety and biocompatibility as compared to several commercial agents.

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In the present study, silver nanoparticles (AgNPs) were synthesized via biological reduction of silver nitrate using extract of the fungus (green chemistry principle). The synthesized nanoparticles were spherical and homogenous in size. AgNPs were coated with polyethylene glycol (PEG) 6000, sodium dodecyl sulfate (SDS), and β-cyclodextrin (β-CD).

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Hepatocellular carcinoma is the second leading cause of cancer deaths worldwide. It is characterized by unique features that can be utilized for selective and targeted therapy, which aids in preserving healthy tissues from deteriorating effects of traditional chemotherapeutics. In this minireview, a brief overview of recent drug delivery attempts for the management of hepatocellular carcinoma with the aid of nanomedical structures is presented.

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Background: Hepaticojejunostomy (HJ) is the classical reconstruction for benign biliary stricture. Endoscopic management of anastomotic complications after hepaticojejunostomy is extremely difficult. In this work we assess a modified biliary reconstruction in the form of bilio-entero-gastrostomy (BEG) regarding the feasibility of endoscopic access to HJ and management of its stenosis if encountered.

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Background: Biliary tract reconstruction continues to be a challenging surgical problem. Multiple experimental attempts have been reported to reconstruct biliary defects with different materials and variable outcome. Our aim was to evaluate a new method for biliary reconstruction using an isolated pedicled gastric tube in a live animal trial and also to present the first clinical case.

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Background: The ongoing debate between routine and selective users of intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC) has not yet come to an end. Routine users argue that IOC decreases the rate of biliary complications such as bile duct injury, biliary leak and missed common bile duct (CBD) stones, a claim that selective users do not fully support. On the other hand, a third policy that was adopted by many other centers is performing LC without IOC.

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Background: Gallstones are more common in patients with liver cirrhosis than in healthy individuals. Higher morbidity and mortality were reported in cirrhotic patients with either laparoscopic or open cholecystectomy. The aim of this study was to compare laparoscopic and open cholecystectomy in cirrhotic patients with symptomatic cholelithiasis in a prospective, randomized manner.

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